Titanium‐Containing Zeolites and Microporous Molecular Sieves as Photovoltaic Solar Cells

Abstract

Four titanium-containing zeolites and microporous molecular sieves differing on the crystal structure and particle size (Ti/Beta, Ti/Beta-60, TS-1 and ETS-10) are prepared, and their activity for solar cells after incorporating N3 (a commercially available ruthenium polypyridyl dye) is tested. All the zeolites exhibit photovoltaic activity, and the photoresponse is quite independent of the zeolite pore dimensions or particle size. The photoresponse increases with titanium content in the range 1-7% wt. In this way, cells are obtained that have open-circuit voltage Voc=560 mV and maximum short-circuit photocurrent density Isc=100 microA, measured for 1x1 cm2 surfaces with a solar simulator at 1000 W through and AM 1.5 filter. These values are promising and comparable to those obtained for current dye-sensitized titania solar cells.

Photovoltaic activity of Ti/MCM‐41

“…[11] and lower than that of a cell based on P-25 TiO 2 . Thus, as can be seen in Table 2, the cell using P-25 TiO 2 exhibits higher overall efficiency.…”

Bathochromic Effects in Electronic Excitation Spectra of Hydrated Ti Zeolites: A Theoretical Characterization

“…A description of the electronic excitation in titanium zeolites in non-oxidizing conditions at an atomistic level is, however, a topic of current interest, as it has been recently reported that titanium zeolites might replace the semiconducting TiO 2 layer in photovoltaic cells. [8] Most of the reported data deals with experiments on TS-1, a zeolite with an MFI framework structure [9] and a unit cell content of [Ti x Si 96Àx O 192 ]-too large for extensive ab initio calculations. As a consequence, a number of theoretical studies have been performed on model clusters or by using embedded cluster approaches (see for example, ref.…”

“…Such a finding raises the challenging question on how an LMCT excitation mechanism alone could account for the semiconducting properties of titanium zeolites exploited in the photovoltaic devices based on titanium zeolites recently described. [8] The LMCT transitions are determined by the relative energies of the titanium-bonded framework oxygen states and titanium d-levels. At the microscopic level, the bathochromic effect on such LMCT spectra is induced by water coordination.…”

Oriented TiO2 Nanostructured Pillar Arrays: Synthesis and Characterization

“…[1,3,[33][34][35][36] Among them, the use of dye-sensitized TiO 2 nanostructures has an outstanding reputation and both experimental and theoretical evaluations of the efficiency-limiting factors have been identified. [33,37,38] Recently, it has been shown that the use of ordered arrays of TiO 2 nanostructures (either pure, such as nanotubes, nanowires, and nanorods [39][40][41] or TiO 2 -based architectures, [15,42,43] which replace the traditional nanoparticle film) can improve the efficiency. [9,34,40,[43][44][45][46][47][48][49] Moreover, it is evident from recent literature data [1,3,9,44,50] that the innovative synthesis of TiO 2 particle arrays, either pure or anchored to conducting substrates, plays a leading role in both photocatalysis and energy conversion applications.…”